His upgrade path will depend on which motherboard he has. Provided that the motherboard will support the necessary FSB, voltage etc. the K6-2 is available in speeds up to 550MHz, and the K6III can still be found up to 450MHz. The K6-2's are not known to be very good prospects for overclocking but I've had good results with the K6III's. Keep in mind that the K6III's have the onboard level 2 cache, making them pretty good performers for their age. I've got a K6III+ 450 @ 616MHz. on an FIC VA503+ board.
Another thing to keep in mind about this platform is it's cost / performance ratio along with it's aging technology, ATA 33 IDE, limited FSB speeds etc.
Since this platform has been out of production for a while some of the parts are getting a bit hard to find and the prices are beginning to creep up, making this aging platform less attractive than a complete overhaul with newer components. Case in point, a socket 7 motherboard will probably cost in the $60.00 to $75.00 range with the CPU costing another $60.00. You can get a basic socket A mother board with onboard sound for less than $80.00 and a 600 - 750MHz DURON for less than $60.00.This approach would give your buddy an upgrade path in the future that will support the newer T-BIRDS up to the 1.2G CPU's for less than $150.00 invested now.
Just a few points to ponder.
Good Luck!
